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Enhanced durability and reactivity for zinc ferrite desulfurization sorbent (open access)

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.
Date: November 14, 1988
Creator: Jha, Mahesh C. & Berggren, Mark H.
Object Type: Report
System: The UNT Digital Library
Eucalyptus plantations for energy production in Hawaii. Technical status report, October 1, 1978-June 30, 1980 (open access)

Eucalyptus plantations for energy production in Hawaii. Technical status report, October 1, 1978-June 30, 1980

Progress made on accomplishing research objectives is reported. The objectives of this project are: (1) to increase the biomass production of Eucalyptus; (2) to determine the optimum requirements to maximize yield; (3) to assess planting, cultivation, harvesting, and transportation equipment requirements; (4) to determine the optimum mixture of biomass (eucalyptus and bagasse) at the generator for the production of electricity; and (5) to evaluate a complete production/conversion system which utilized optimum management conditions in relationship to costs. (DMC)
Date: July 14, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Considerations of bunch-spacing options for multi-bunch operation of the Tevatron Collider (open access)

Considerations of bunch-spacing options for multi-bunch operation of the Tevatron Collider

This discussion will consider a number of points relevant to limitations, advantages and disadvantages of various arrangements of bunches in the Tevatron proton-antiproton collider. The considerations discussed here will be limited to: (a) bunch spacing symmetry and relation to the relative luminosity at B0 and D0 and the beam-beam interaction with separated beams; (b) bunch spacing constraints imposed by Main Ring RF coalescing and the optics of beam separation at B0 and D0; and (c) bunch spacing constraints imposed by injection and abort kicker timing requirements, and by the Antiproton Source RF unstacking process. 20 figs., 17 tabs.
Date: December 14, 1989
Creator: Dugan, G.
Object Type: Report
System: The UNT Digital Library
Development of copper sulfide/cadmium sulfide thin film solar cells. First technical progress report, 13 July 1979 to 12 October 1979 (open access)

Development of copper sulfide/cadmium sulfide thin film solar cells. First technical progress report, 13 July 1979 to 12 October 1979

Preparation of CdS films by evaporation from a single graphite source, as generally used by the Institute of Energy Conversion (IEC) group at the University of Delaware, has been implemented. Previously at Westinghouse, four evaporation sources were used to permit uniform coverage of large area substrates. The graphite source used in this period is somewhat smaller than the IEC design to permit accommodation to the heater geometry currently available. Initial efforts with the single source evaporation have been on characterizing the thickness profiles of the deposited films. This is needed to permit selection of conditions for obtaining films of about 30..mu..m thickness over the central 4 cm x 4 cm area of the substrate. Barrier processing according to the details of IEC method has been used on four-source CdS films. To date the best cells have only been about 1% efficient. Low short circuit current density values (approx. 5 mA/cm/sub 2/) have been the biggest problem. Annealing in 6% H/sub 2//Ar mixtures at 170/sup 0/C after electrode grid evaporation generally has resulted in reduced values of J/sub sc/. Plans for the next period include the use of single source films for cell processing and the use of small area diode …
Date: February 14, 1980
Creator: Szedon, J. R.; Shirland, F. A.; Stoll, J. A. & Dickey, H. C.
Object Type: Report
System: The UNT Digital Library
Analysis of the new GCFR upper and lower plenum flow-through shields (open access)

Analysis of the new GCFR upper and lower plenum flow-through shields

Analysis of the proposed GCFR upper and lower plenum flow-through shields has been performed using both discrete ordinate (DOT) and Monte Carlo (MORSE) methods. Several shields having one change of direction in the coolant path (chevron) and two changes of direction (herringbone) were investigated. The shields were modeled as unit cells with periodic boundary conditions. From plenum fluence calculations and design constraints at the reactor vessel liner, it was determined that all the shield configurations analyzed should be adequate for the necessary radiation attenuation.
Date: September 14, 1980
Creator: Cramer, S.N. (Oak Ridge National Lab., TN); Reed, D.A.; Emmett, M.B. & Rouse, C.A.
Object Type: Article
System: The UNT Digital Library
Geothermal aquaculture project: Real Property Systems Inc. , Harney Basin, Oregon (open access)

Geothermal aquaculture project: Real Property Systems Inc. , Harney Basin, Oregon

Real Property Systems Inc., (RPS) owns two parcels in the vicinity of Harney Lake, Oregon. One parcel is 120 acres in size, the other is 200 acres. A study concludes that the 200 acre parcel has the greater potential for geothermal development. RPS is interested in an aquaculture operation that produces fresh water prawns, (Macrobrachium rosenbergii) for the market. To supply the heat necessary to maintain the ideal temperature of 82/sup 0/F desired for these prawns, a geothermal resource having a 150/sup 0/F temperature or higher, is needed. The best estimate is that 150/sup 0/F water can be found from a minimum 1090 feet depth to 2625 feet, with no absolute assurances that sufficient quantities of geothermal waters exist without drilling for the same. This study undertakes the preliminary determination of project economics so that a decision can be made whether or not to proceed with exploratory drilling. The study is based on 10 acres of ponds, with a peak requirement of 2500 gpm of 150/sup 0/F geothermal water.
Date: August 14, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Quantitative study of mixing in annular and raschig ring filled tanks (open access)

Quantitative study of mixing in annular and raschig ring filled tanks

A quantitative study of mixing, which utilized the exit age distribution theory, has been completed for bench-scale annular and raschig ring filled tanks, in addition to a pilot-scale annular tank. A study of mixing and fluid flow in a full-scale, single-entry, raschig ring filled tank also was initiated. Results showed the bench-scale raschig ring filled tank approached plug-flow (no mixing) behavior. In a bench-scale annular tank, regardless of whether fluid entered tangentially or nontangentially, the vessel approached continuously stirred tank reactor behavior (perfect mixing). The pilot-scale annular tank approached continuously stirred tank reactor behavior only when tangential entry was used. Mixing in the full-scale raschig ring filled tank he tank did not approach eithr the perfect or the no mixing situations. Instead, the tank had a flow pattern in which solution channeled through a small volume of the tank, leaving the regions outside the channel effectively inactive.
Date: July 14, 1980
Creator: Fredrickson, M. A.
Object Type: Report
System: The UNT Digital Library
The shell model approach: Key to hadron structure (open access)

The shell model approach: Key to hadron structure

A shell model approach leads to a simple constituent quark model for hadron structure in which mesons and baryons consist only of constituent quarks. Hadron masses are the sums of the constituent quark effective masses and a hyperfine interaction inversely proportional to the product of these same masses. Hadron masses and magnetic moments are related by the assumption that the same effective mass parameter appears in the additive mass term, the hyperfine interaction, and the quark magnetic moment, both in mesons and baryons. The analysis pinpoints the physical assumptions needed for each relation and gives two new mass relations. Application to weak decays and recent polarized EMC data confirms conclusions previously obtained that the current quark contribution to the spin structure of the proton vanishes, but without need for the questionable assumption of SU(3) symmetry relating hyperon decays and proton structure. SU(3) symmetry breaking is clarified. 24 refs.
Date: August 14, 1989
Creator: Lipkin, H.J. (Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Nuclear Physics)
Object Type: Article
System: The UNT Digital Library
Induction linacs as radiation processors (open access)

Induction linacs as radiation processors

Experiments at the Lawrence Livermore National Laboratory (LLNL), University of California, in conjunction with the University of California at Davis have shown induction linear accelerators (linacs) to be suitable for radiation processing of food. Here we describe how it might be possible to optimize this technology developded for the Department of Defense to serve in radiation processing. The possible advantages of accelerator-produced radiation over the use of radioisotopes include a tailor-made energy spectrum that can provide much deeper penetration and thereby better dose uniformity.
Date: April 14, 1986
Creator: Birx, D.L.
Object Type: Report
System: The UNT Digital Library
Linear and non-linear calculations of the hose instability in the ion-focused regime (open access)

Linear and non-linear calculations of the hose instability in the ion-focused regime

A simple model is adopted to study the hose instability of an intense relativistic electron beam in a partially neutralized, low density ion channel (ion focused regime). Equations of motion for the beam and the channel are derived and linearized to obtain an approximate dispersion relation. The non-linear equations of motion are then solved numerically and the results compared to linearized data.
Date: June 14, 1982
Creator: Buchanan, H.L.
Object Type: Report
System: The UNT Digital Library
Large area silicon sheet by EFG. Annual progress report, October 1, 1978-September 30, 1979 (open access)

Large area silicon sheet by EFG. Annual progress report, October 1, 1978-September 30, 1979

The progress which has been made in 1978/1979 to evolve systems designs for growth stations which produce multiple silicon ribbons by the EFG process is reported. This progress culminated in the demonstration of five ribbon multiple growth in May 1979 and in recent advances toward improved electronic quality of ribbons grown from these machines. These advances were made in large measure by studies in which the composition of the gas environment around the meniscus area was varied. By introducing gases such as CO/sub 2/, CO, and CH/sub 4/ into this region, reproducible increases in diffusion length and cell performance have been realized, with the best large area (5 cm x 10 cm) cells exceeding 11% (AM1) efficiency.
Date: March 14, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Classical geometrical interpretation of ghost fields and anomalies in Yang-Mills theory and quantum gravity (open access)

Classical geometrical interpretation of ghost fields and anomalies in Yang-Mills theory and quantum gravity

The reinterpretation of the BRS equations of Quantum Field Theory as the Maurer Cartan equation of a classical principal fiber bundle leads to a simple gauge invariant classification of the anomalies in Yang Mills theory and gravity.
Date: May 14, 1985
Creator: Thierry-Mieg, J.
Object Type: Article
System: The UNT Digital Library
Multifragmentation in intermediate energy heavy ion collisions (open access)

Multifragmentation in intermediate energy heavy ion collisions

The GSL/LBL plastic ball/wall detector system was used to gain insight into the fragment production mechanism in Au + Au and Au + Fe reactions. Full azimuthal coverage for light particles (p,d,t,/sup 3/He,/sup 4/He) and intermediate mass fragments (z greater than 10) is achieved in the forward hemisphere in the center of mass system. The complete measurement of light particles allowed a global analysis of the events and a search for collective effects in fragment emission by comparing to flow effects seen in the light particles. The large acceptance for intermediate mass fragments allowed a measurements of their multiplicities event-by-event.
Date: April 14, 1986
Creator: Jacak, B. V.; Britt, H. C.; Claesson, G.; Doss, K. G. R.; Ferguson, R.; Gavron, A. I. et al.
Object Type: Report
System: The UNT Digital Library
OTEC cold water pipe design for problems caused by vortex-excited oscillations (open access)

OTEC cold water pipe design for problems caused by vortex-excited oscillations

Vortex-excited oscillations of marine structures result in reduced fatigue life, large hydrodynamic forces and induced stresses, and sometimes lead to structural damage and to diestructive failures. The cold water pipe of an OTEC plant is nominally a bluff, flexible cylinder with a large aspect ratio (L/D = length/diameter), and is likely to be susceptible to resonant vortex-excited oscillations. The objective of this report is to survey recent results pertaining to the vortex-excited oscillations of structures in general and to consider the application of these findings to the design of the OTEC cold water pipe. Practical design calculations are given as examples throughout the various sections of the report. This report is limited in scope to the problems of vortex shedding from bluff, flexible structures in steady currents and the resulting vortex-excited oscillations. The effects of flow non-uniformities, surface roughness of the cylinder, and inclination to the incident flow are considered in addition to the case of a smooth cyliner in a uniform stream. Emphasis is placed upon design procedures, hydrodynamic coefficients applicable in practice, and the specification of structural response parameters relevant to the OTEC cold water pipe. There are important problems associated with in shedding of vortices from cylinders …
Date: March 14, 1980
Creator: Griffin, O. M.
Object Type: Report
System: The UNT Digital Library
Improved photoelectrodialytic cell (open access)

Improved photoelectrodialytic cell

A multicompartment photoelectrodialytic demineralization cell is provided with a buffer compartment interposed between the product compartment and a compartment containing an electrolyte solution. Semipermeable membranes separate the buffer compartment from the product and electrolyte compartments. The buffer compartment is flushed to prevent leakage of the electrolyte compartment from entering the product compartment.
Date: August 14, 1981
Creator: Murphy, G.W.
Object Type: Patent
System: The UNT Digital Library
Effects of space charge on the acceptance of brightness measuring devices (open access)

Effects of space charge on the acceptance of brightness measuring devices

Attempts to measure high electron beam brightness at low values of beam energy are plagued by the effects of space charge forces. These forces can substantially lower the phase space acceptance of various brightness measuring devices. This report considers several models for the effects of space charge upon the acceptance of both the field free, double aperture system and the magnetic ''emittance selector'' and compares them for some recent experiments on ATA and the High Brightness Test Stand. Reasonably conservative correction factors for the acceptances of these devices are derived.
Date: August 14, 1985
Creator: Caporaso, G.J.
Object Type: Report
System: The UNT Digital Library
Commercial synthesis of M97KVB gum, a precursor to cellular silicone cushions. Part I (open access)

Commercial synthesis of M97KVB gum, a precursor to cellular silicone cushions. Part I

The technology for producing an LLNL-developed polymer, L97KVB, has been transferred to a commercial speciality silicones manufacturer, McGhan-NuSil Corporation. Workers there have demonstrated both on a small scale and on a 200 lb. scale that they can produce a polymer which meets our analytical specifications and which will also perform satisfactorily in our load deflection and compression set tests.
Date: May 14, 1982
Creator: Riley, M.O.; Kolb, J.R. & Jessop, E.S.
Object Type: Article
System: The UNT Digital Library
Polyacetylene, (CH)/sub x/, as an emerging material for solar cell applications. Technical progress report, October, November, December 1979 (open access)

Polyacetylene, (CH)/sub x/, as an emerging material for solar cell applications. Technical progress report, October, November, December 1979

Initial studies of p-n heterojunctions formed between undoped trans-(CH)/sub x/ and n-CdS are reported. The junctions were characterized by measurements of current vs voltage (I-V), capacitance vs voltage (C-V), and photovoltaic response spectra. The results are analyzed in terms of the standard heterojunction equations. It is concluded that undoped as-grown films of trans-(CH)/sub x/ are p-type with a residual acceptor concentration of 2 x 10/sup 18/ cm/sup -3/, and that in spite of the complex fibril morphology the semiconductor properties can be inferred by treating (CH)/sub x/ as an effective homogeneous medium. Detailed studies of the photovoltaic response at energies below the energy gap for (CH)/sub x/ imply the existence of a well-defined deep trapping state in polyacetylene with an energy near the center of the gap.
Date: February 14, 1980
Creator: Heeger, A.J. & MacDiarmid, A.G.
Object Type: Report
System: The UNT Digital Library
Progress on axicell MFTF-B superconducting magnet systems (open access)

Progress on axicell MFTF-B superconducting magnet systems

Since the entire Mirror Fusion Test Facility (MFTF-B) Magnet System was reconfigured from the original A-cell to an axicell design, much progress has been made on the design, fabrication, and installation planning. The axicell MFTF-B magnet array consists of a total of 26 large superconducting main coils. This paper provides an engineering overview of the progress of these coils. Recent studies on the effects of field errors on the plasma at the recircularizing region (transition coils) show that small field errors will generate large displacements of the field lines. These field errors might enhance radial electron heat transport and deteriorate the plasma confinement. Therefore, 16 superconducting trim coils have been designed to correct the coil misalignments. Progress of the trim coils are reported also.
Date: November 14, 1983
Creator: Wang, S. T.; Kozman, T. A.; Hanson, C. L.; Shimer, D. W.; VanSant, J. H. & Zbasnik, J.
Object Type: Article
System: The UNT Digital Library
Concentrations of dissolved methane (CH sub 4 ) and nitrogen (N sub 2 ) in groundwaters from the Hanford Site, Washington (open access)

Concentrations of dissolved methane (CH sub 4 ) and nitrogen (N sub 2 ) in groundwaters from the Hanford Site, Washington

This document reports all available dissolved gas concentration data for groundwaters from the Hanford Site as of June 1985. Details of the computational procedures required to reduce data obtained from the field measurements made by the Basalt Waste Isolation Project are provided in the appendix. Most measured values for methane concentration from reference repository boreholes are in the range of from 350 to 700 mg/L for the Cohassett flow top. Because of the uncertainties associated with these measurements, it is currently recommended that a conservative methane concentration of 1200 mg/L (methane saturated) in groundwater be considered the most reasonable upper-bounding value. 16 refs., 2 figs., 2 tabs.
Date: March 14, 1986
Creator: Early, T.O.
Object Type: Report
System: The UNT Digital Library
Acoustical heat-pumping engine (open access)

Acoustical heat-pumping engine

The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium.
Date: August 14, 1981
Creator: Wheatley, John C.; Swift, Gregory W. & Migliori, Albert
Object Type: Patent
System: The UNT Digital Library
Detonator-activated ball shutter (open access)

Detonator-activated ball shutter

A detonator-activated ball shutter for closing an aperture in about 300 ..mu..seconds is disclosed. The ball shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the ball shutter, thereby blocking passage through the aperture.
Date: May 14, 1981
Creator: McWilliams, R. A. & Von Holle, W. G.
Object Type: Patent
System: The UNT Digital Library
Campus to open math, science academy (open access)

Campus to open math, science academy

Newspaper article by Nancy Mathis detailing the opening of the Texas Academy of Mathematics and Science in Denton, Texas.
Date: July 14, 1987
Creator: Mathis, Nancy
Object Type: Clipping
System: The UNT Digital Library
[Memo from Rogers W. Redding to James R. Miller, September 14, 1987] (open access)

[Memo from Rogers W. Redding to James R. Miller, September 14, 1987]

Memo from Rogers W. Redding to James R. Miller, on September 14, 1987, sending a curriculum vitae of Dr. Julian C. Stanley.
Date: September 14, 1987
Creator: Redding, Rogers W.
Object Type: Letter
System: The UNT Digital Library